Log In
Portsmouth Mine, Cuyuna North Range, Crow Wing County, Minnesota, USAi
| Regional Level Types | |
|---|---|
| Portsmouth Mine | Mine (Flooded) |
| Cuyuna North Range | Mountain Range |
| Crow Wing County | County |
| Minnesota | State |
| USA | Country |
This page is currently not sponsored. Click here to sponsor this page.
Latitude & Longitude (WGS84):
46° 29' 22'' North , 93° 57' 59'' West
Latitude & Longitude (decimal):
Type:
Mine (Flooded) - last checked 2023
Köppen climate type:
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
Local clubs are the best way to get access to collecting localities
| Club | Location | Distance |
|---|---|---|
| Cuyuna Rock, Gem and Mineral Society | Brainerd, Minnesota | 23km |
Other/historical names associated with this locality:
Portsmouth Extension
The Portsmouth mine is one of the largest open pits in the district; the pit has been formed by the combination of several smaller pits and underground mines: Portsmouth, SE1/4SE1/4 sec. 2; Wearne, SW1/4SE1/4 sec. 2; Osberg, SE1/4SW1/4 sec. 2; Chisholm-Williams, NW1/4NW1/4 sec. 11; Evergreen, NE1/4NW1/4 sec. 11; Healy, formerly part of Thompson, NW1/4NE1/4 sec. 11; and Meacham, NE1/4NE1/4 sec. 11. Development of the Portsmouth ore body began with the northward crosscutting from the Thompson underground mine into the northern part of the NW1/4NE1/4 sec. 11 in 1912 or 1913. The Wearne mine, SW1/4SE1/4 sec. 2, was stripped as an open pit in 1916. From the Portsmouth mine 13,127,832 tons were shipped through 1955, exclusive of ore mined from the Thompson mine.
The pit, eventually over 1,200 feet wide and nearly 2 miles long, exposed a thick and multiple repeated section of complexly folded Proterozoic Trommald Banded Iron Formation. Both oxidized and unoxidized ore occurred. Also exposed was a titaniferous argillite body of enigmatic origin. The deep mine pit was a popular launch site for high altitude balloon flights in the 1950's. The flooded pit and overgrown dumps of the mine site are now a major part of the Cuyuna Country State Recreation area. It is administered by the Minnesota Department of Natural Resources, and no collecting is permitted.Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsCommodity List
This is a list of exploitable or exploited mineral commodities recorded from this region.Mineral List
Mineral list contains entries from the region specified including sub-localities10 valid minerals.
Rock Types Recorded
Rock list contains entries from the region specified including sub-localities
Select Rock List Type
Alphabetical List Tree DiagramDetailed Mineral List:
| ⓘ Aragonite Formula: CaCO3 References: |
| ⓘ 'Chlorite Group' References: |
| ⓘ Goethite Formula: Fe3+O(OH) References: |
| ⓘ Grunerite Formula: ◻Fe2+2Fe2+5(Si8O22)(OH)2 References: |
| ⓘ Hematite Formula: Fe2O3 |
| ⓘ Kutnohorite Formula: CaMn2+(CO3)2 References: |
| ⓘ Magnetite Formula: Fe2+Fe3+2O4 |
| ⓘ Pyrite Formula: FeS2 References: |
| ⓘ Quartz Formula: SiO2 |
| ⓘ Siderite Formula: FeCO3 |
| ⓘ Stilpnomelane Formula: K4Fe2+48[Si64Al8]O164(OH)52 · nH2O |
| ⓘ 'Tourmaline' Formula: AD3G6(T6O18)(BO3)3X3Z |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 2 - Sulphides and Sulfosalts | |||
|---|---|---|---|
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Magnetite | 4.BB.05 | Fe2+Fe3+2O4 |
| ⓘ | Hematite | 4.CB.05 | Fe2O3 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| ⓘ | Goethite | 4.FD.10 | Fe3+O(OH) |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Siderite | 5.AB.05 | FeCO3 |
| ⓘ | Kutnohorite | 5.AB.10 | CaMn2+(CO3)2 |
| ⓘ | Aragonite | 5.AB.15 | CaCO3 |
| Group 9 - Silicates | |||
| ⓘ | Grunerite | 9.DE.05 | ◻Fe2+2Fe2+5(Si8O22)(OH)2 |
| ⓘ | Stilpnomelane | 9.EG.40 | K4Fe2+48[Si64Al8]O164(OH)52 · nH2O |
| Unclassified | |||
| ⓘ | 'Chlorite Group' | - | |
| ⓘ | 'Tourmaline' | - | AD3G6(T6O18)(BO3)3X3Z |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Goethite | Fe3+O(OH) |
| H | ⓘ Grunerite | ◻Fe22+Fe52+(Si8O22)(OH)2 |
| H | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
| B | Boron | |
| B | ⓘ Tourmaline | AD3G6(T6O18)(BO3)3X3Z |
| C | Carbon | |
| C | ⓘ Aragonite | CaCO3 |
| C | ⓘ Kutnohorite | CaMn2+(CO3)2 |
| C | ⓘ Siderite | FeCO3 |
| O | Oxygen | |
| O | ⓘ Aragonite | CaCO3 |
| O | ⓘ Goethite | Fe3+O(OH) |
| O | ⓘ Grunerite | ◻Fe22+Fe52+(Si8O22)(OH)2 |
| O | ⓘ Hematite | Fe2O3 |
| O | ⓘ Kutnohorite | CaMn2+(CO3)2 |
| O | ⓘ Magnetite | Fe2+Fe23+O4 |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Siderite | FeCO3 |
| O | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
| O | ⓘ Tourmaline | AD3G6(T6O18)(BO3)3X3Z |
| Al | Aluminium | |
| Al | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
| Si | Silicon | |
| Si | ⓘ Grunerite | ◻Fe22+Fe52+(Si8O22)(OH)2 |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
| S | Sulfur | |
| S | ⓘ Pyrite | FeS2 |
| K | Potassium | |
| K | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
| Ca | Calcium | |
| Ca | ⓘ Aragonite | CaCO3 |
| Ca | ⓘ Kutnohorite | CaMn2+(CO3)2 |
| Mn | Manganese | |
| Mn | ⓘ Kutnohorite | CaMn2+(CO3)2 |
| Fe | Iron | |
| Fe | ⓘ Goethite | Fe3+O(OH) |
| Fe | ⓘ Grunerite | ◻Fe22+Fe52+(Si8O22)(OH)2 |
| Fe | ⓘ Hematite | Fe2O3 |
| Fe | ⓘ Magnetite | Fe2+Fe23+O4 |
| Fe | ⓘ Pyrite | FeS2 |
| Fe | ⓘ Siderite | FeCO3 |
| Fe | ⓘ Stilpnomelane | K4Fe482+[Si64Al8]O164(OH)52 · nH2O |
Other Databases
| Wikipedia: | https://en.wikipedia.org/wiki/Portsmouth_Mine_Pit_Lake |
|---|---|
| Wikidata ID: | Q7232478 |
| Link to USGS MRDS: | 10121901 |
Localities in this Region
- Minnesota
- Crow Wing County
- Cuyuna North Range
- Crow Wing County
Other Regions, Features and Areas containing this locality
This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to
visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders
for access and that you are aware of all safety precautions necessary.
References
Quick NavTopCommoditiesMineral ListRock TypesOther DatabasesLocalities in RegionOther RegionsReferences
Portsmouth Mine, Cuyuna North Range, Crow Wing County, Minnesota, USA